Drafting instrument



Spff. N9 w3., s. s. CARY f DRAFTING INSTRUMENT Filed Sept. 8, 1934 Patented Sept. 17, 1935 UNITED STATS DRAFTING INSTRUMENT Samuel S. Cary, Jennings, La.

Application September 8, 1934, Serial No. 743,283

4 Claims. (Cl. 33-20) This invention relates to the class of drafting 5 are each provided with an inwardly directed instruments and pertains particularly to a deflange 6 and between the plates is slidably disvice for facilitating the drawing of contours. posed a two-part block "l, which is provided with The primary object of the present invention grooves 8 upon opposite faces to slidably receive 5 is to provide a device which is designed to be used the flanges e, as illustrated in Figure 3. The 5 upon a plane table and which may beV used in block 'l has a chamber i) therein in which is roconjunction with a compass and range finder, tatabiy disposed a relatively broad gear wheel whereby an object or horizon contour may be te, and passages i i and l2 extend, respectively, sighted and transferred through mechanism opvertically and horizontally through the block 'l 10 erating in coordination with the sighting mechand have communication with the gear chamber 10 anism to a drawing paper disposed upon the plane e, as illustrated in Figure 3. The table has a slot table. Y i3 therein, which extends parallel with the back Another object of the invention is to provide a edge and lies beneath the slot Il, and the plates drawing instrument wherein a horizontally movt and 5 are also provided With lengtlldnally eX- able marker or scribe is coupled with a vertically tending slots which are indicated by the numeral 15 and horizontally movable sighting element te, which are in the same plane as the passage whereby the movement of the sighting element i2 in the block l.

either vertically or horizontally will be trans- EXtehdng lengtudnally 0f and between the ferred through the scribing element to a drawplates and 5 iS a Shaft t5 0f DOlygOnal CIOSS ing paper located therebeneath, SeCtOll Wl'llCll (JaSSeS through the gear l2 and iS 20 The invention will be best understood from a I'etatably SUDDOTted at tS ends in the hearings consideration of the following detailed descripit. The gear i0 iS Sldable 0n this shaft but cantion taken in connection with the accompanying net IOtate independently thereOf- At One end, drawing forming part of this specication, with the shaft i5 has a beveled gear l'! thereon which the understanding, however, that the invention meshes with a similar gear i3 mounted UDOII the 25 is not conned to any strict conformity with the Shaft i9 Which eXteIlds from the Year edge of the showing of the drawing but may be' changed or table to the forward edge thereof, where it iS inodiiied so long as such changes or modifications supported by the bearing Z0 and carries a hand mark no material departure from the salient fea- Wheel 2|. The end of the shaft i9 which car- Y tures of the invention asexpressed in the apries the gear te passes through and is supported 30 pended o1aim5 by the inner plate 5. Disposed at the opposite In the drawing; side of the table from the shaft i9 is a shaft 22 Figure 1 is a View in top plan of the instru- Which is supported, as indicated at 23, adjacent mom; embodying the present invention, the front edge of the table and carries upon the Figure 2 is a sectional View taken on the line end adjacent this edge the hand Wheel 24. The 35 2 2 of Figure 1 rear end of the shaft 22 passes through and is Figure 3 is a sectional view taken on Athe line Supported by the plates 4 and 5 and carries a 3--3 of Figure 1. sprocket wheel 25. At the opposite end of the Figure 4 is a view in elevation of a stationary plate t lOIn the end adjacent the SDI'OCket Wheel sight forming a part of the instrument, 25, is mounted a similar sprocket wheel 26, and 40 Referring to the drawing, the numeral inthese wheels have a sprocket chain 2i passing dicates a working surface of any suitable Charthereover and connected with the block i, as inacter such, for example, as a plane table, which deated at 25- It Will thus he apparent that by is normally supported upon a, tripod, the legis 0f rotating the hand Wheel 24, the Sprocket Chain which are indicated by the numerals 2, upon Will be Caused t0 IIlOVe OVeI the Wheels 25 and 25 45 which table or Work surface, the mechanism emand Shift the gear Carrying block 1. body-ing thepresent invention is shown mounted Extending horizontally over the surface of the The present invention comprises a guide of any tablet and passing through the passage l2 of the suitable character which is here indicated by block and the passages le of the plates 4 and 5,

the numeral 3 and illustrated as comprising a is a rack bar 2S which has its teeth in engagement 50 pair of plates i and 5 xed in spaced parallel with the teeth oi the gear le. This bar constirelation to the table to extend across one edge tutes a marker carrying arm having at its inner of the same, which edge constitutes the back of end a suitable socket or other means 3i] for rethe table when the present instrument is in use. ceiving and holding a pencil or other suitable These elongated plates or guide elements i and marker 3l which extends downwardly toward the 55 top surface of the table. Extending vertically through the slot I3 of the table and through the passage l l of the block 1 is a second rack bar which is indicated by the numeral 32, and which also has its teeth in engagement with the teeth of the wheel l0. This bar 32 constitutes a movable sight bar, the upper end being formed to provide a sight 33, which is here illustrated as being in the form of a ring or eye.

At the front edge of the table l and preferably at the center of this edge is mounted a xed sight bar or standard 34, the upper end of which carries an eye or other suitable sight 35 for use in association with the sight 33 of the movable sight bar.

From the foregoing, it is believed to be apparent that in the operation of the present instrument, after a drawing paper has been ,secured to the table I, the table is positioned between the user and the object which is to be outlined upon the paper with the movable sight bar 32 between the object and the fixed bar 34. By then lining up the sights 33-35 with the edge of the object to be outlined on the paper and manipulating the hand wheels 2 lV and 24, the sight 33 can be caused to follow the outline of the object, and it will be apparent that every movement of this sight will be transferred to the scribing bar or arm 29, and the marker 3l will be caused to move over the surface of the drawing paper and thus outline the object thereon.

What is claimed iszl. An instrument, comprising a drawing surface, guide means extending along one side of said surface, a body mounted upon said guide means for movement along said side, an arm carried by said body and movable in a plane paralleling said surface and at right angles to the direction of movement of the body, a vertical member carried by said body and movable vertically therethrough, means carried by the body coupling said vertical member and said arm whereby vertical movement of the said member will be effected simultaneously with reciprocatory movement of said arm, a sight carried by the vertical member, a marker carried by and fixed to the arm, a fixed sight disposed at the opposite side of the surface from the sight upon said member, means for .effecting movement of said body, and means for effecting simultaneous movement of the arm and member.

2. An instrument of the character described, comprising a work surface, means forming a pair of guides in parallel relation at one side of said surface, a body slidably mounted on and between said guides, a gear rotatably carried by the body, a shaft paralleling the guides and having sliding connection with said gear, means for rotating the shaft from a point at the opposite side of the work surface from the guides, a rack member passing through the body and dispose vertically and having toothed connection with the gear, a 5

rack member passing through the body and paralleling the work surface and having toothed connection with the gear, a sight carried by said vertical rack member, a marker carried by the horizontal rack member, a fixed sight disposed at the opposite side of the work surface from the vertical rack, and means operable from the opposite side of the work surface from the body for effecting the movement of the body in either direction on said guides. 3. An instrument of the character described, comprising a board constituting a work surface, a body mounted on said board, supporting means for said body facilitating its movement in a path adjacent an edge of the board, a pair of elongated members extending at right angles through said body, one of said members being disposed at right angles to the surface of the board and the other of said members being disposed parallel to the board surface te extend across the same, means carried by said vertical member at its upper end providing a sight, a marker fixed to the member paralleling the board at the end overlying the board, means carried by said body and coupling said members whereby the members 3l)AV may be moved longitudinally in unison, means facilitating the manipulation of the member coupling means from a point remote from the body, means facilitating the movement of the body and the elongated members carried thereby on said supporting means, from a point remote from the body, and a fixed sight carried by the board for coaction with the rst sight.

4. An instrument of the character described, comprising a drawing surface, a body disposed at one side of the drawing surface, means supporting said body facilitating its movement along the said side of the drawing surface, means for effecting the movement of the body, a pair of arm members disposed in right angular relation one thereof overlying and extending parallel with the drawing surface, said arms passing through said body, a marker carried by the said one of the arms, a sight carried by the other one of said arms, an element carried by said body and having movement relative thereto and coupling said anns whereby movement of the element will effect the simultaneous longitudinal movement of the arms, means for effecting the movement of the element, and a second sight xed relative to the arm carried 5 5 sight.

SAMUEL S. CARY. 

